1. Technical Field
The present invention relates to an optical memory system, more specifically to a data recording method in a holography optical memory system.
2. Description of the Related Art
Nowadays, the optical discs have widely been popular as data-recording mediums. The optical discs require the technology that can decrease the diameter of a beam spot to increase the recording density and decrease the distance between adjacent tracks or adjacent bits. The recording density of the optical disc, however, has recently reached the physical limitation due to the diffraction of light.
Accordingly, the holography optical memory has come into the spotlight as the next-generation memory for replacing recording mediums such as optical discs. The holography optical memory features high capacity attributed to 3-dimensional multi-recording and high speed attributed to 2-dimensional batch-recording and reproducing. Described below is the method of recording and reproducing data in the holography optical memory.
Firstly, if a signal beam, corresponding to data which will be recorded in the recording medium such as photorefractive crystal or photo polymer, and a reference beam cross each other, an interference pattern according to the interference between the two beams is formed and recorded as the change of the refractive index. Later, it is possible to reproduce (or restore) the recorded data by illuminating the recording medium with the reference beam only.
However, there may be some errors in the process of recording and reproducing data in the holography optical memory system. This may yield disadvantageous effects on the precision and reliability of the memory system.
In accordance with the conventional art, there has been an attempt to solve the above problem by creating an additional error-correcting code such as the Reed Solomon code and then storing the error-correcting code in the recording medium together. The conventional art, however, requires complex pre-treatment processes for creating the error-correcting code and an additional device for encoding the error-correcting code.